Multi-stage type air cleaner



Oct. 22, 1935. H. G. KAMRATH 2,018,13l

MULTISTAGE TYPE AIR CLEANER Filed Nov. so. 1928 gwmzntofo M5/ma f entoure ijf,

Patented Oct. y32,1935

PATENT orricla'.l

MULTI-STAGE TYPE am CLEANER Herbert G. Kamath, Flint, Mich., assigner, by

mesne assignments, to General Motors Corporation, Detroit, Mich., a corporation of Dela- Application November 30, 1928, Serial No. 322,848'

4Claims.

'I'his invention relates to air cleaners of the multi-stage type.

As is well known, air cleaners of the dry or liquid wetted lter type are much more eiilcient than those of other types in'removing foreign matter from the air to be cleaned. However, where the air to be cleaned contains excessive amounts of foreign matter, simple air cleaners of the lter type are not entirely satisfactory for the reason that, after a comparatively short period of use, they become clogged with foreign matter.

It is an object of this invention to provide an air cleaner which, while retaining all of the good features of air cleaners of theiilter type, is not liable to become-clogged when used where it is required to remove excessive amounts of foreign from a perusal of the following description of the preferred embodiment of my' invention which is shown in the accompanying drawing. In the drawing: K

Figure lis a vertical section, taken on the line I.I of Figure 2, through'an air cleaner of the multi-stage type.

Figure 2 is a top plan view, with parts broken away' and in section, of the air cleaner shown in Figure 1.

In itsv preferred embodiment, asl shown in the my air cleaner includes a cup portion III, a .dust-'collecting element II, a vane element I2, and a cover portion Il.

The cup portion I `is provided on its open end with anoutwardly extending circumferential flange I4, and intermediate its open and closedl :adsl swith an inwardly extending circumferential The dust collecting element II includes a central tube i 6, a cylindrical shell I'I coaxial with and surrounding one end of the central tube, and spiders I8 secured to opposite ends of the shell and to one end andan intermediate portion of the tube to secure the VShell and tube together in spaced relation. 'I'he annular Space between the central tube I8, the shell 11, and the spidersl` by an outwardly projecting collar 26.

is filled with a suitable oil-coated dust-collecting medium I9. The dust-collecting medium I9 preferably consists of a cartridge of fabric, woven or knitted from at copper ribbon, of the type disclosed in my copending application S. N.

245,404, filed January 9, 1928 which has matured into Patent No. 1,829,401, dated October 27, 1931. To eliminate the tendency of the dust-collecting medium to work out of the shell through the spaces between the legs of the spiders, annular 10 members of wire screen are preferably provided. t

'I'he dust-collecting element I I is made of such size as to fit snugly within the open end of the cup portion ill with its lower end seated and 15 supported on the rib I 5 and with its upper end at substantially the level of flange I4.` When the parts are thus assembled, as shown in the drawing, the upper end of the central tube I6 projects upwardly beyond the open end of the cup por- 2o tion I0.

Within the central tube IB is located the vane element I2 which consists of a plurality of helical vanes 2| suitably secured together so as to form, in effect.- a single member. The edges of the vanes 2I are frictionally engaged with the wall of the tube so that the vane element I2 may be adjusted to and remain in any desired position in the tube.

The cover portion I3 consists of a generally 30 cup-shaped member through the closed endof which extends an opening 23 surrounded by an inwardly projecting collar 24 and through the side wall of which extends an opening 25 surrounded The cover portion I3 is assembled with the cup portion III, the dust-collecting element I I, and the vane element i2, as shown in the drawing, with the flange I II voi the cup portion seated in a rabbet 21 in the side wall of the cover` portion ad- 40 jacent its open end, and with the upwardly projecting end of the central tube I6 snugly telescoped within the collar`24. The cover portion is secured to the 'cup portion by means of the bolts 28,` which extend throughv brackets 29 secured to 45 the cup portion adjacent its open end and through .tion and the dust-collecting element. 'I'he spring is preferably made of such diameter that it will fit snugly around the upper end of the collar 24 so that it will not be likely t0 be displaced therefrom and lost when the cleaner is dismantled.

The type of air cleaner hereinbefore described, although obviously susceptible of use in other installations, is peculiarly adapted for use in cleaning' the air to be supplied to the carburetor of a tractor of the type which is provided with a vertical stack or air intake conduit extendingv from the air intake conduit of the carburetor to a point above the zone of dust raised by the tractor. When used in such an installation, the air cleaner is positioned between the air intake conduit of the carburetor and the stack, with the opening 25 in the cover communicating with the former and with the opening 23 in the cover with the latter.

When the air cleaner is in use, a'supply of oil or other suitable liquid is maintained in the bottom of the cup portion Il). During the operation of the tractor, the suction produced in the engineV cylinders draws air through the stack into the air cleaner through the opening 23 and, thence, into the central tube I6. During Vits passage through the central tube I6,- the air impinges against the vanes 2| which cause it to travel in a helical path, and enter the lower part of the cup portion I0 with a whirling motion. The whirling motion of the air as it enters the lower part of the cup portion I 0 causes a portion of the foreign matter carried thereby to be thrown by centrifugal action against the oil-coated side walls of the cup portion to which it adheres and is thus removed from the air. I'he downward velocity of the air causes it to impinge against the surface of the body of liquid within the lower part-of the cup portion and the whirling motion thereof causes the impact to be distributed more or less evenly over a large part of the surface of the liquid. As the air impinges against the surface of the liquid, another portion of the foreign matter carried thereby is brought into contact with the liquid and adheres thereto and is thereby removed from the air. After impinging against the surface of the liquid, the air reverses its direction of ow, and, due to the fact that momentum of the particles of. foreign matter carried by the air is greater than that of the air they are not able to reverse their direction of travel as quickly as the air and so some of them are carried by their momentum against the surface of the liquid to which they adhere and are thereby removed from the air. After reversing its direction of ow, the air, from which it will be obvious the greater proportion of the foreign matter has been removed,

passes into the annular space between the central tube I6 and the`cylindrical shell. I1, through the interstices in the oil-coated dust-collecting medium I9, and into the space between the dust-collecting element and the closed end of the cover I3, whence it passes to the carburetor and engine cylinders. During its passage through the dustv collecting medium I9, any foreign matter, including any particles of oil which may be picked up by the air from the supply in the lower part of the cup portion I0, carried by the air are' deposited on and retained by the oil-coated surface of the dust-collecting medium, with the result that the air passing into the carburetor and engine cylinders is free from foreign matter.

The vane element I2 may be adjusted, as previously mentioned, to any desired position in the central tube I6 in order to vary the force of the impact of the air on the Asurface of the liquid in the lower part of the cup portion I Il, or, if for any reason it is felt desirable, may be dispensed with entirely. It is obvious, without explanation, that my air cleaner may be quickly and easily dismantled when this is necessary in order to clean it or to replace the liquid supply in the lower part of `the cup portion I0 when it has become fouled with foreign matter or reduced to too small a voltions which may be necessary havebeen performed, it mayl'ust as easilybe reassexnbled'.`

Althoughl have Ya., preierred embodiment of vrxiyvinven'tion, it is to'l be understood that this has 'beenfnonemerelfby Way of example, and that'thev scope ofrriyfifri-V .tacle below the dust-collecting element, a vane element within the passage, and an air discharge opening in the cover.

2. In an air cleaner of the multi-stage type, an open-ended liquid receptacle. a conduit extending into the open end of the receptacle and from which air to be cleaned is adapted to be discharged onto the surface of the liquid, an annular open-ended dust collecting element through which the air is adapted to pass occupying the space between the walls of the conduit and the side walls of the receptacle and a vane element in the conduit arranged to cause the air emerging therefrom to impinge against an area oi' the surfaceof the liquid substantially greater than the cross sectional area of the conduit.

3. In an air cleaner which includes a cupshaped body, a cover which closes the open end of the body and through which an air intake opening extends, and a unitary assembly, including a dust-collecting element and an air intake conduit which extends therethrough and communicates with the air intake opening in the ume by loss, and that,`after any of these operar` Y cover; clamped between the body and the cover.`

4. An air filter comprising a casing, filter material therein, a wall extending through the cas" ing means in said air inlet.

HERBERT G. KAMRATH.\ 

